Conventionally known as a laser processing method of this kind is one in which an expandable holding member (expandable tape or the like) holding a wafer-like object to be processed is directly secured by suction onto a suction table of a vacuum chuck, and the object is irradiated with laser light while locating a converging point within the object, so as to form a modified region within the object along a line to cut (see, for example, Patent Document 1).
Patent Document 1: Japanese Patent Application Laid-Open No. 2004-179302